As long-time affordable housing developers and community builders, we believe in the ideal of mixed-income communities. We have experienced genuine success in our work within communities, as well as authentic moments of personal growth and fun in our personal lives by living side by side with diverse neighbors. We have observed people from very different backgrounds getting to know each other in new ways by exchanging small favors of value, and we have watched a site staff team hold small-group “design sessions” with diverse residents to solve a shared problem. The truth is, however, that these moments have been hard won and few and far between. This may be no wonder, given the huge human and financial resources committed to bricks-and-mortar development compared with the limited ingenuity and investment devoted to sorting out the complex human aspects of daily operations and community building in contexts where residents come from very different cultural and class backgrounds. There is no doubt that this is the hardest part of this work to figure out—but we must.